MATLAB Object-Oriented Programming

Class Support for Array-Creation Functions

In this section...

“Extend Array-Creation Functions for Your Class” on page 9-38

“Which Syntax to Use” on page 9-39

“Implement Support for Array-Creation Functions” on page 9-40

Extend Array-Creation Functions for Your Class

There are several MATLAB functions that create arrays of a specific size and type, such as

ones and zeros. User-defined classes can add support for array-creation functions

without requiring the use of overloaded method syntax.

Class support for any of the array-creation functions enables you to develop code that you

can share with built-in and user-defined data types. For example, the class of the variable

x in the following code can be a built-in type during initial development, and then be

replaced by a user-defined class that transparently overloads zeros:

cls = class(x);

zArray = zeros(m,n,cls);

Array-creation functions create arrays of a specific type in two ways:

• Class name syntax — Specify class name that determines the type of array elements.


• Prototype object syntax — Provide a prototype object that the function uses to
  determine the type and other characteristics of the array elements.

For example:

zArray = zeros(2,3,'uint8');

p = uint8([1 3 5 ; 2 4 6]);

zArray = zeros(2,3,'like',p);

After adding support for these functions to a class named MyClass, you can use similar

syntax with that class:

zArray = zeros(2,3,'MyClass');

Or pass an object of your class:

9 Methods — Defining Class Operations